In the Linux kernel, the following vulnerability has been resolved:
libceph: reset sparse-read state in osd_fault()
When a fault occurs, the connection is abandoned, reestablished, and any
pending operations are retried. The OSD client tracks the progress of a
sparse-read reply using a separate state machine, largely independent of
the messenger's state.
If a connection is lost mid-payload or the sparse-read state machine
returns an error, the sparse-read state is not reset. The OSD client
will then interpret the beginning of a new reply as the continuation of
the old one. If this makes the sparse-read machinery enter a failure
state, it may never recover, producing loops like:
libceph: [0] got 0 extents
libceph: data len 142248331 != extent len 0
libceph: osd0 (1)...:6801 socket error on read
libceph: data len 142248331 != extent len 0
libceph: osd0 (1)...:6801 socket error on read
Therefore, reset the sparse-read state in osd_fault(), ensuring retries
start from a clean state.
In the Linux kernel, the following vulnerability has been resolved:
of: unittest: Fix memory leak in unittest_data_add()
In unittest_data_add(), if of_resolve_phandles() fails, the allocated
unittest_data is not freed, leading to a memory leak.
Fix this by using scope-based cleanup helper __free(kfree) for automatic
resource cleanup. This ensures unittest_data is automatically freed when
it goes out of scope in error paths.
For the success path, use retain_and_null_ptr() to transfer ownership
of the memory to the device tree and prevent double freeing.
In the Linux kernel, the following vulnerability has been resolved:
tracing: Add recursion protection in kernel stack trace recording
A bug was reported about an infinite recursion caused by tracing the rcu
events with the kernel stack trace trigger enabled. The stack trace code
called back into RCU which then called the stack trace again.
Expand the ftrace recursion protection to add a set of bits to protect
events from recursion. Each bit represents the context that the event is
in (normal, softirq, interrupt and NMI).
Have the stack trace code use the interrupt context to protect against
recursion.
Note, the bug showed an issue in both the RCU code as well as the tracing
stacktrace code. This only handles the tracing stack trace side of the
bug. The RCU fix will be handled separately.
In the Linux kernel, the following vulnerability has been resolved:
netfilter: nf_conncount: update last_gc only when GC has been performed
Currently last_gc is being updated everytime a new connection is
tracked, that means that it is updated even if a GC wasn't performed.
With a sufficiently high packet rate, it is possible to always bypass
the GC, causing the list to grow infinitely.
Update the last_gc value only when a GC has been actually performed.
In the Linux kernel, the following vulnerability has been resolved:
netfs: Fix early read unlock of page with EOF in middle
The read result collection for buffered reads seems to run ahead of the
completion of subrequests under some circumstances, as can be seen in the
following log snippet:
9p_client_res: client 18446612686390831168 response P9_TREAD tag 0 err 0
...
netfs_sreq: R=00001b55[1] DOWN TERM f=192 s=0 5fb2/5fb2 s=5 e=0
...
netfs_collect_folio: R=00001b55 ix=00004 r=4000-5000 t=4000/5fb2
netfs_folio: i=157f3 ix=00004-00004 read-done
netfs_folio: i=157f3 ix=00004-00004 read-unlock
netfs_collect_folio: R=00001b55 ix=00005 r=5000-5fb2 t=5000/5fb2
netfs_folio: i=157f3 ix=00005-00005 read-done
netfs_folio: i=157f3 ix=00005-00005 read-unlock
...
netfs_collect_stream: R=00001b55[0:] cto=5fb2 frn=ffffffff
netfs_collect_state: R=00001b55 col=5fb2 cln=6000 n=c
netfs_collect_stream: R=00001b55[0:] cto=5fb2 frn=ffffffff
netfs_collect_state: R=00001b55 col=5fb2 cln=6000 n=8
...
netfs_sreq: R=00001b55[2] ZERO SUBMT f=000 s=5fb2 0/4e s=0 e=0
netfs_sreq: R=00001b55[2] ZERO TERM f=102 s=5fb2 4e/4e s=5 e=0
The 'cto=5fb2' indicates the collected file pos we've collected results to
so far - but we still have 0x4e more bytes to go - so we shouldn't have
collected folio ix=00005 yet. The 'ZERO' subreq that clears the tail
happens after we unlock the folio, allowing the application to see the
uncleared tail through mmap.
The problem is that netfs_read_unlock_folios() will unlock a folio in which
the amount of read results collected hits EOF position - but the ZERO
subreq lies beyond that and so happens after.
Fix this by changing the end check to always be the end of the folio and
never the end of the file.
In the future, I should look at clearing to the end of the folio here rather
than adding a ZERO subreq to do this. On the other hand, the ZERO subreq can
run in parallel with an async READ subreq. Further, the ZERO subreq may still
be necessary to, say, handle extents in a ceph file that don't have any
backing store and are thus implicitly all zeros.
This can be reproduced by creating a file, the size of which doesn't align
to a page boundary, e.g. 24998 (0x5fb2) bytes and then doing something
like:
xfs_io -c "mmap -r 0 0x6000" -c "madvise -d 0 0x6000" \
-c "mread -v 0 0x6000" /xfstest.test/x
The last 0x4e bytes should all be 00, but if the tail hasn't been cleared
yet, you may see rubbish there. This can be reproduced with kafs by
modifying the kernel to disable the call to netfs_read_subreq_progress()
and to stop afs_issue_read() from doing the async call for NETFS_READAHEAD.
Reproduction can be made easier by inserting an mdelay(100) in
netfs_issue_read() for the ZERO-subreq case.
AFS and CIFS are normally unlikely to show this as they dispatch READ ops
asynchronously, which allows the ZERO-subreq to finish first. 9P's READ op is
completely synchronous, so the ZERO-subreq will always happen after. It isn't
seen all the time, though, because the collection may be done in a worker
thread.
In the Linux kernel, the following vulnerability has been resolved:
iommu/sva: invalidate stale IOTLB entries for kernel address space
Introduce a new IOMMU interface to flush IOTLB paging cache entries for
the CPU kernel address space. This interface is invoked from the x86
architecture code that manages combined user and kernel page tables,
specifically before any kernel page table page is freed and reused.
This addresses the main issue with vfree() which is a common occurrence
and can be triggered by unprivileged users. While this resolves the
primary problem, it doesn't address some extremely rare case related to
memory unplug of memory that was present as reserved memory at boot, which
cannot be triggered by unprivileged users. The discussion can be found at
the link below.
Enable SVA on x86 architecture since the IOMMU can now receive
notification to flush the paging cache before freeing the CPU kernel page
table pages.
In the Linux kernel, the following vulnerability has been resolved:
dpll: Prevent duplicate registrations
Modify the internal registration helpers dpll_xa_ref_{dpll,pin}_add()
to reject duplicate registration attempts.
Previously, if a caller attempted to register the same pin multiple
times (with the same ops, priv, and cookie) on the same device, the core
silently increments the reference count and return success. This behavior
is incorrect because if the caller makes these duplicate registrations
then for the first one dpll_pin_registration is allocated and for others
the associated dpll_pin_ref.refcount is incremented. During the first
unregistration the associated dpll_pin_registration is freed and for
others WARN is fired.
Fix this by updating the logic to return `-EEXIST` if a matching
registration is found to enforce a strict "register once" policy.
In the Linux kernel, the following vulnerability has been resolved:
wifi: ath12k: fix dead lock while flushing management frames
Commit [1] converted the management transmission work item into a
wiphy work. Since a wiphy work can only run under wiphy lock
protection, a race condition happens in below scenario:
1. a management frame is queued for transmission.
2. ath12k_mac_op_flush() gets called to flush pending frames associated
with the hardware (i.e, vif being NULL). Then in ath12k_mac_flush()
the process waits for the transmission done.
3. Since wiphy lock has been taken by the flush process, the transmission
work item has no chance to run, hence the dead lock.
>From user view, this dead lock results in below issue:
wlp8s0: authenticate with xxxxxx (local address=xxxxxx)
wlp8s0: send auth to xxxxxx (try 1/3)
wlp8s0: authenticate with xxxxxx (local address=xxxxxx)
wlp8s0: send auth to xxxxxx (try 1/3)
wlp8s0: authenticated
wlp8s0: associate with xxxxxx (try 1/3)
wlp8s0: aborting association with xxxxxx by local choice (Reason: 3=DEAUTH_LEAVING)
ath12k_pci 0000:08:00.0: failed to flush mgmt transmit queue, mgmt pkts pending 1
The dead lock can be avoided by invoking wiphy_work_flush() to proactively
run the queued work item. Note actually it is already present in
ath12k_mac_op_flush(), however it does not protect the case where vif
being NULL. Hence move it ahead to cover this case as well.
Tested-on: WCN7850 hw2.0 PCI WLAN.HMT.1.1.c5-00302-QCAHMTSWPL_V1.0_V2.0_SILICONZ-1.115823.3
In the Linux kernel, the following vulnerability has been resolved:
platform/x86: hp-bioscfg: Fix kobject warnings for empty attribute names
The hp-bioscfg driver attempts to register kobjects with empty names when
the HP BIOS returns attributes with empty name strings. This causes
multiple kernel warnings:
kobject: (00000000135fb5e6): attempted to be registered with empty name!
WARNING: CPU: 14 PID: 3336 at lib/kobject.c:219 kobject_add_internal+0x2eb/0x310
Add validation in hp_init_bios_buffer_attribute() to check if the
attribute name is empty after parsing it from the WMI buffer. If empty,
log a debug message and skip registration of that attribute, allowing the
module to continue processing other valid attributes.